Hi Simon, On Sat, Oct 11, 2025 at 11:52 PM Simon Glass <[email protected]> wrote: > > Hi Tony, > > On Sat, 11 Oct 2025 at 20:41, Tony Dinh <[email protected]> wrote: > > > > On Sat, Oct 11, 2025 at 7:37 AM Tom Rini <[email protected]> wrote: > > > > > > On Sat, Oct 11, 2025 at 01:03:39PM +0100, Peter Robinson wrote: > > > > On Fri, 10 Oct 2025 at 15:28, Tom Rini <[email protected]> wrote: > > > > > > > > > > On Thu, Oct 09, 2025 at 10:29:17PM -0700, Tony Dinh wrote: > > > > > > > > > > > Make it possible to disable CMD_PXE. > > > > > > Remove unnecessary PXE_UTILS selection in BOOTMETH_EXTLINUX config. > > > > > > In extlinux_boot(), invoke pxe utils only when > > > > > > CONFIG_BOOTMETH_EXTLINUX_PXE is enabled. > > > > > > > > > > > > This patch results in about 9K reduction in image size when > > > > > > PXE boot is disabled. > > > > > > > > > > > > Signed-off-by: Tony Dinh <[email protected]> > > > > > > --- > > > > > > > > > > > > boot/Kconfig | 3 +-- > > > > > > boot/bootmeth_extlinux.c | 18 ++++++++++-------- > > > > > > 2 files changed, 11 insertions(+), 10 deletions(-) > > > > > > > > > > Is some part of the symbol logic here wrong? A challenge is that "PXE" > > > > > is also where the logic to parse extlinux.conf style files came from, > > > > > and I thought we had split those two out. And then there's this: > > > > > > > > > > > > > > > > > diff --git a/boot/Kconfig b/boot/Kconfig > > > > > > index 2993cd7f9ba..403ce4c3d46 100644 > > > > > > --- a/boot/Kconfig > > > > > > +++ b/boot/Kconfig > > > > > > @@ -421,10 +421,10 @@ config BOOT_DEFAULTS_CMDS > > > > > > select CMD_PART if PARTITIONS > > > > > > select CMD_DHCP if CMD_NET > > > > > > select CMD_PING if CMD_NET > > > > > > - select CMD_PXE if CMD_NET > > > > > > select CMD_BOOTI if ARM64 > > > > > > select CMD_BOOTZ if ARM && !ARM64 > > > > > > imply CMD_MII if NET > > > > > > + imply CMD_PXE if CMD_NET > > If you only want scripts, then perhaps you can enable just what you > need, e.g. BOOTMETH_SCRIPT? You may need to disable BOOT_DEFAULTS and > choose your own options.
Indeed, that was a missing config when I tried with BOOTSTD_FULL disabled. But there is more, please see below. > > > > > > > > > > > This is one of the things where defaults isn't supposed to be so easy > > > > > to > > > > > get out of. How many platforms are you wanting to then disable CMD_PXE > > > > > on to save space? > > > > > > > > PXE is generally being removed in a lot of cases as it's not > > > > considered secure and now we have HTTP Boot there are other means of > > > > doing network booting so I think we'll see more and more situations > > > > where we want to disable PXE. > > > > > > > > This is actually something I've been meaning to look at so it's > > > > something I would love to see :) > > > > Glad to hear :) > > > > > > > > And in the world where we also can't just remove ATAGS support because > > > distros (Debian at least) still boots some modern platforms via ATAGS + > > > appended device tree, the high level options for "boot this anywhere" > > > need to perhaps be different from "very modern requirements only > > > distro". I'm not objecting to be clear. > > > > As Tom suggested previously, perhaps looking from a different angle. > > We can disable BOOTSTD_FULL and then try adding only options that are > > needed for a board. Unfortunately this approach did not work when I > > tried it in the past. It seems for bootstd to work well, we need to > > take the whole thing by enabling BOOTSTD_FULL. > > If you end up trying it again, please give a few details here as we > might be able to improve this. When bootstd was first introduced we > had very tight code-size constraints, so quite a few features are only > provided if BOOTSTD_FULL is enabled. Tom has suggested enabling more > features in the base implementation but we haven't really figured out > which. The problem is when a board already has enabled BOOTSTD_FULL or has been updated with Distro Boot (CONFIG_DISTRO_DEFAULTS), all the necessary configurations such as ext2, ext4, efi partition,... are implied, therefore were removed from board defconfig. They must be added back. I actually tried this just now and it does work booting a script from USB drive with this combination: CONFIG_BOOTMETH_SCRIPT=y CONFIG_DISTRO_DEFAULTS=y (this also selects CMD_PXE, but it's OK for this test) # CONFIG_BOOTSTD_FULL is not set I think it's quite cumbersome to add each of the necessary configs back to the board defconfig. Not as easy as removing CMD_PXE, or other CMD_x to remove a capability. All the best, Tony > > Regards, > Simon
